Mixed fungicide preparation



United States Patent 3,226,290 MHXED FUNGECIDE PREPARATEUN Gustave K.Kuhn, llerlreley, (Ialifi, assignor to Chevron Research Company, acorporation of Delaware No Drawing. Filed .lune l, 1962, Ser. No.199,237 4 Claims. (Cl. 16733) This invention relates to a novel methodof preparing fungicides. More particularly, this invention relates to anew method of preparing multiple component fungicides havingN-acyl-N-polyhaloalkylthio and/or Nacyl-N-polyalkyldithio groups.

In many agricultural applications, it is preferred to use a number ofbiologically active compounds, rather than a single compound. In a fewsituations, the mixing is found to result in a synergistic effect. Thatis, the combination has a much higher activity than the simple additionof the activities of its par-ts. The synergism is usually derived from acombination of chemical and biological effects.

It has now been found that a synergistic effect may be obtained by themethod of combining the substituents, rather than from the specificspecies that are combined. The enhanced activity is achieved bypreparing the various components of the fungicidal mixturesimultaneously in the same reaction mixture in a solvent in which theproduct is relatively insoluble and the components coprecipitate. Thisis illustrated by the following equation:

T1 T1 m IM Rl IM X(s)..Y [Rl I(S)nY'RI T(S)nY] where R and R aredifferent acyl groups, T and T are the same or different substituents ashereinafter described, N is nitrogen, M is a metal or hydrogen, X ishalogen, S is sulfur, It varies from 1 to 2, and Y is a polyhaloalkylgroup. (The brackets and dot indicate that the two components are inintimate combination.) Of course, the nitrogen compound could bemaintained constant and the thio compound varied as illustrated by thefollowing equation:

T T 'r RIL M X(s),.Y X(s) Y [RI 1'(S),1Y-RI \l(S)nY'] The symbols havethe same meaning as indicated above, and Y is a polyhaloalkyl groupdifferent from Y. Final- 1y, one could use a plurality of nitrogencompounds and thio compounds, obtaining a complex crystalline product.

The physical situation in the reaction mixture is the existence of twoliquid phases, the sulfenyl halide phase and the polar, usually aqueousphase, which contains the acyl substituted nitrogen compound. When morethan one sulfenyl halide is used, the sul-fenyl halides form ahomogeneous phase which is dispersed through the polar phase. Uponreaction between the sulfenyl halide compounds and the acyl substitutednitrogen compound, the insoluble product rapidly crystallizes out as anintimate combination.

The sulfur containing precursors to the final compound which find use inthis invention are polyhaloalkylsulfenyl halides andpolyhaloalkylthiosulfenyl halides. The polyhaloalkyl group is a loweralkyl group, that is, of from 1 to 6 carbon atoms and, preferably, of atleast 3 halogens, one of which is bonded to the carbon bonded to sulfur.The preferred compounds are those alkyl groups having up to andincluding 2 carbon atoms. These compounds are illustrated by thefollowing generic formula:

l 3 m( )n where Z is hydrogen or halogen of atomic number 17 to 35, X ishalogen of atomic number 17 to 35, with the proviso that at least one Xis bonded to the carbon ice bonded to sulfur, l=2(m1), m varies from 1to 2 and n varies from 1 to 2. The halogens of atomic number 17 to 35are chlorine and bromine. The polyhalomethylsulfenyl and thiosulfenylhalides have the following formula:

and the polyhaloethylsulfenyl and thiosulfenyl halides have thefollowing formula:

where the symbols are as defined previously.

Sulfenyl halides which are operative in this invention include suchcompounds as trichloromethylsulfenyl chloride,brornodichloromethylsulfenyl bromide, l,1,2-trichloroethylsulfenylchloride, 1,2,2 trichlor-oethylsulfenyl chloride,1,2dibromo-1,2-dichloroethylsulfenyl chloride, 1,2-dibromol,2,2-trichloroethylsulfenyl chloride, perchloroethylsulfenyl chloride,1,2,3-trichloropropylsulfenyl chloride, perchlor-opropylsulfenylchloride, 1,l,2,3-tetrachloropropylsulfenyl chloride,1,1,2-trichlo-robutylsulfenyl chloride and 1,2,3,4-tetrachlorobutylsulfenyl chloride. Examples of thiosulfenyl halideswhich find use in this invention are trichloromethylthiosulfenylbromide, bromodichloromethylthiosulfenyl chloride,1,.1,2,2-tetrachloroethylthiosulfenyl chloride,l,2-dibromo-1,2-dichloroethylthiosulfenyl chloride,perchloroethylthiosulfenyl chloride and1,2,2-trichloropropylthiosulfenyl chloride.

The nitrogen precursor is an acyl substituted amine or its metal salt,that is, an amide or imide having an acidic hydrogen or their salts.Acyl groups include carboxyl and sulfonyl groups. The acyl nitrogencompounds used in this invention have the following formula:

R-NM

where R is an acyl group; T is hydrogen or an organic radical which maybe alkyl, aryl, alicyclic, aralkyl, alkaryl and acyl, and when joinedwith R forms a ring with the nitrogen; and M is hydrogen or an alkali oralkaline earth metal cation, the particularly preferred metals beinglithium, sodium and potassium.

The R and T groups should preferably be individually not more than 10carbons, and when joined together not more than 15 carbons. Particularlypreferred is R of not more than 8 carbons and R and T combined of notmore than 8 carbons. R and T may be substituted by halogen, nitro,alkoxy, etc., but are preferably hydrocarbon, except for the acylfunctionality.

R may be an aliphatic acid such as acetyl, butyryl, decanoyl; aromaticacids such as benzoyl, toluyl, naphthoyl; and sulfonic acids such asethylsulfonyl, tolylsulfonyl, etc.

T may be hydrogen as when R is sulfonyl; however, it is preferred that Tnot be hydrogen but alkyl, such as methyl, ethyl, octyl; aryl such asphenyl, tolyl and naphthyl; alicyclic such as cyclopentyl andcyclohexyl; and acyl such as exemplified by R.

When R and T are taken together, they join to form a ring as exemplifiedby monocyclic imides, such as succinimide, glutarimide, suberimide,hydantoin, 5,5-dimethylhydantoin, etc., and bicyclic imides such asphthalimide, 1,2- naphthadioylirnide, 4 tetrahydrophthalimide, 1tetrahydrophthalimide, etc.

The preferred groups of compounds are those in which R is arylsulfonyland T is hydrogen, alkyl or aryl and those in which R and T are takentogether to form monoand bicyclic heterocycles of up to and including 8carbons. R and T taken together may form .a hydrocarbon chain as inglutarimide or a hetero chain containing one nitrogen other than theimide nitrogen as in hydantoin.

R and T may also form a hydrocarbon chain which forms a second ring asin phthalimide.

The preferred sulfonamide salts have the formula A-M wherein M is analkali or alkaline earth metal and A is a nitrogen-containing group ofthe formula:

RSOzN- where R is alkyl or aryl of not more than 8 carbons, T ishydrogen, alkyl or aryl of not more than 8 carbons and M is as definedpreviously. This includes such compounds as sodioN-methyl-p-tolylsulfonamide, lithio N-pchlorophenylbenzenesulfonamide,potassio N octyl 2,4- xylylsulfonamide, etc.

The preferred monocyclic imides have the formula AM wherein M is analkali or alkaline earth metal and A is a nitrogen-containing group ofthe formula:

(2) O l f where R T is a hydrocarbon chain of not more than 6 carbons ora hetero chain having not more than 1 nitrogen and usually of not morethan 6 carbons.

The preferred bicyclic imides have the formula A-M wherein M is analkali or alkaline earth metal and A is a nitrogen-containing group ofthe formula:

where A and A are the same or different nitrogen-containing groups aspreviously defined above in Formulas 1, 2 and 3, and Y and Y may be thesame or different and are of the formula:

where Z, X, l, m and n are as defined previously. Of course, if Y and Yare the same, then either R or R or T or T must be different in orderthat there be present two distinct compounds in the composition.

Examples of mixtures which find. use in this invention are such mixturesas N-trichloromethylthiophthalimide andN-pentachloroethylthiophthalimide; N-1,2,2-trichloroethylthiohydantoinand N-l,1,2,2-tetrachloroethylthiohydantoin;N-methyl-N-bromodichloromethylthiobenzenesulfonamide andN-methyl-N-1,2-dibromo-1,2-dichloroethylthiobenzenesulfonamide;N-trichloromethylthiosuccinimide and N-trichloromethylthio-A-tetrahydrophthalimide;

N-pentachloroethylthiosuccinimide andN-pentachloroethylthio-M-tetrahydrophthalimide;N-1,l,2-trichloroethylthiosulfenyl-p-nitrobenzenesulf0namide andN-l,2,2-trichloropropylthiosulfenyl-p-nitrobenzenesulfonamide;N-trichloromethylthiosulfenyl-N,N-diacetylimide andN-1,2,3,4-tetrachlorobutylthiosulfenyl-N,N-diacetylimide.

While mixtures having only 2 components are preferred, mixtures having 4components are intended to be included in this invention. Of course, anynumber of components could be made, but these would probably serve onlyspecific situations.

In preparing formulations according to this invention, one or moreamides or imides or their metal salts are dissolved in a solvent whichis a nonsolvent for the final product. When the amides or imides areused, a strong base is added to the mixture and. the mixture stirreduntil all the solids go into solution. One or a mixture of more than onesulfenyl or thiosulfenyl halides is then added with vigorous stirring tothe previously described solution. The coprecipitated product,therefore, has at least two distinct compounds present.

The mixture will usually be cooled and vigorous agitation continued forabout 2 minutes to 2 hours. The mixture is then filtered, washed with anonsolvent and. dried.

The solvent is limited by the requirement that it be a solvent for thenitrogen precursor, but a nonsolvent for the final compounds and heinert to the reactants and products. The most convenient solvent iswater and is preferred. Other polar solvents which might be used arelower alkanols at relatively low temperatures, e.g., about 0 C., ethers,and mixed solvents with water, etc. By virtue of the insolubility of theproduct in the liquid media and vigorous agitation, tiny crystals areobtained which are sufiiciently small to be used directly as fungicides,crystals of a mean size of 1 to 10 are obtained.

The temperature of the reaction is not critical and, subject to thelimitation that the solvent must remain an unreactive liquid and theproduct solubility is not significantly enhanced, may vary from -15 to50 C. Preferred temperatures are in the range 0 to 20 C.

The time for the reaction is not critical, usually being in excess of 2minutes. No advantage is found in an extended time period and agitationwill usually be stopped within 2 hours.

By controlling the proportions of the reactants, the amounts of thevarious components may be widely varied from less than 1% to greaterthan 99%, depending on the characteristics desired for the resultingformulation, however, it is preferred to have at least 10% of onecomponent.

As an illustration of the variations in specific compositions, thefollowing examples are presented. It is to be understood that thecompositions prepared in these examples are merely representative andare not to be construed as limitations on the scope of the invention.

Example I To a mixture of water and ice in a Waring Blendor was added15.1 g. (0.1 mol) tetrahydrophthalimide and 9.6 g. 50% caustic andstirred until all the organic material dissolved. A solution containing9.3 g. perchloromethyl mercaptan (Cl CSCl) (0.05 mol) and 11.7 g.1,1,2,2- tetrachloroethylsulfenyl chloride (0.05 mol) was slowly addedto the aqueous solution with vigorous agitation. Ice was added tomaintain the temperature about 0 C. The mixture was agitated for 30minutes, filtered, washed with warm water, methanol and petroleum ether,respectively, and dried. The product weighed 21.2 g. (65% theory). Thematerial had a melting range of 129 to C.

The following is a tabular compilation of mixtures prepared according toExample I.

TABLE I Nitrogen Compound Sulfcnyl Halide Mol proportion 0013801110012001 8012. 50 50 IICCIECCIZSCIL 25 75 HCCMCCI SCI 75 25 CClaSCl 5050 HCCl CCl SCI 50 5O HGClzCClzSCl 50 50 hydantoin. VIIL.Tetrahydrophthaldo.-. ECO/120012801 50 50 irnide. IX PhthalimideCClaSSCl HCClzCCliSSCl 50 50 Mixtures prepared in the manner previouslydescribed were tested as to their activity in the control of variousfungus caused plant diseases. A mechanical mix of the components wasalso tested.

Tomato, celery and bean plants were used. All the lants were in at leastthe three-leaf stage. The test plants were passed through a spraychamber and sprayed at approximately 20 p.s.i. with an aqueou suspensionof a candidate fungicide at the desired dilution. After spraying, theplants were allowed to remain in an exhaust chamber until they dried.The plants were then inoculated with an aqueous suspension of thedesignated pathogen. an incubation chamber for a sufficient period oftime, usually about 18 hours, and then transferred to a holding room fora sufiicient time to allow optimum development of the symptoms of thedisease.

At the end of this time, the disease readings were the present inventionand a mechanical mixture of the components of the composition. The EDand ED indicate the parts per million of the fungitoxic chemical whichmust be used to obtain 50 and 84% control, respectively.

The inoculated plant was then put in 30 Aside from the specificformulation and application of the class of compositions of theinvention as represented by the foregoing tests, these compositions maybe dispersed in or upon other inert liquid and solid carniers such asinert clay, xylenes, etc. The solid carriers may be in the form of adust, or used in conjunction with a suitable wetting agent to form awettable powder. The fungitoxic compositions of the invention may alsobe formulated with other solvents, dispersing agents, or emulsifyingagents. Further, these compositions may not only be applied alone butmay also be used in combination with other active toxicants in theformulation of fungicidal compositions.

The compositions may be applied to any environmental area which is ahost to fungus or susceptible to fungus attack. For example, thefungicidal compositions may be sprayed or otherwise applied directly toa plant or other host, may be applied to the plant seed, sprayed uponthe soil or other plant environment, or used in similar ways so a toeffect the control of fungus and fungus-cased diseases.

The surprising improvement in properties is not understood. There was noreason to anticipate any activity increase in preparing the compoundstogether or preparing them separately and then combining themsubsequently. That an advantage is obtained by applicants method ofpreparation is evident from Table II.

As will be evident to those skilled in the art, various modifications ofthis process can be made or followed, in the light of the foregoingdisclosure and discussions, without departing from the spirit or scopeof the dis closure or from the scope of the following claims.

Mechanical mix .r AB Reaction product Mechanical mix" AB Reactionproduct Mechanical mix AC Reaction product Mechanical mix BD Reactionproduct Mechanical mix... DE Reaction product Mechanical mix CE Reactionproduct Mechanical mix 1 A-N-1,1,2.2-tetrachloroethylthiotetrahydrophthalimidc.

BN-trichloromethylthio tetrahydrophthalimide.* C-3-(N-1,1,2,2-tetrachloroethy]thio)-5,5dimethylhydantoin.D-N-trichloromethylthio phthalirnide.* E-NJ,1,2,2-tetrachloroethylthiophthalimide.

2 The mechanical mix was prepared by mixing the desired proportions ofthe components in a commercial blender for a period of about 15 to 20minutes.

These compounds were obtained as commercially available. The compoundswere, therefore, in a physical form optimized for maximum activity whenused in the mechanical mix.

7 8 I claim: are dissolved in said aqueous medium when only one 1. Amethod for preparing a fungitoxic product having species of said organicsulfur compound is used in fungitoxic activity greater than the sumtotal of its comthe preparation; thereby forming at least one groupponents, of the formulae which comprises dissolving in an aqueous mediuma salt of at least one acidic nitrogen compound of the forand [A(S)nY A(S)Y] mula AM wherein M is a member of the group [A(S) Y,A(S) consistingof alkali and alkaline earth metals and n n A is a member selected fromthe class of nitrogenwherein A and different members Selected containinggroups consisting of: from the class consisting of nitrogen-containing(1) T1 groups of Formulas 1, 2 and 3 as previously defined, n is aspreviously defined, and Y and Y RS01N are different polyhaloalkyl groupsof the formula wherein R is a substituent of not more than 8 car- Z X Cwherein Z, X, l and m are as previously bons and is selected from thegroup consisting of defined. alkyl and aryl hydrocarbon and T is asubstituent 2. Method for preparing a fungitoxic product having of notmore than 8 carbons and is selected from the fungitoxic activity greaterthan the sum total of its comgroup consisting of hydrogen, alkyl andaryl hydroponents, carbon; which comprises dissolving in an aqueousmedium a (2) O salt of at least 1 acidic nitrogen compound of the Hformula: TB/ 1! N- R3C\ NH II T o 0 wherein R T is selected from thegroup consist- 0 ing of 2)2, 2)3, 2 wherein R T is a monocyclichydrocarbon group and -(CH CNH; and containing a ring of 5 to 6 carbonsand a total of not (3) 0 more than 8 carbons;

il adding at a temperature in the range of -15 to 50 C.

with vigorous agitation trichloromethylsulfenyl chloride andl,1,2,2-tetrachloroethylsulfenyl chloride, of T C the formula 5 0wherein R --T is a monocyclic hydrocarbon group RLL R A containing aring of 5 to 6 carbons and a total of not I I more than 8 carbons; TLCadding to said aqueous medium at a temperature in H H the range of from-15 to 50 C., with vigorous agi- 0 0 gitrron, at least one organicsulfur compound of the wherein Y is trichloromethyl, is mula 3 T3 l d fid l 3 m( chloroethyl and R Is as prevlousy e ne 3. A product prepared asdescribed 1n clalm 1. wherein Z is selected from the group consisting of4 A d t prepared as d ib d i l i 2 hydrogen and halogen of atomic number17 to 35, 1 and X is halogen of atomic number 17 to 35, with ReferencesCited by the Examiner the proviso that at least one X is bonded to thecarbon bonded to sulfur, l=2(m1), m is of from 1 UNITED STATES PATENTSto 2 and n is of from 1 to 2; and with the further 83 2 53 3 2 provisothat at least two dlfierent species of said ,775 5/ 9 H y t a 167 3organic sulfur compound are added when only one species of said acidicnitrogen compound salt is dissolved in said aqueous medium and at leasttwo dif- JULIAN LEVITT P r 1mm y Examiner ferent species of said acidicnitrogen compound salt L. GOTTS, Examiner. v

1. A METHOD FOR PREPARING A FUNGITOXIC PRODUCT HAVING FUNGITOXICACTIVITY GREATER THAN THE SUM TOTAL OF ITS COMPONENTS, WHICH COMPRISESDISSOLVING IN AN AQUEOUS MEDIUM A SALT OF AT LEAST ONE ACIDIC NITROGENCOMPOUND OF THE FORMULA A-M WHEREIN M IS A MEMBER OF THE GROUPCONSISTING OF ALKALI AND ALKALINE EARTH METALS AND A IS A MEMBERSELECTED FROM THE CLASS OF NITROGENCONTAINING GROUP CONSISTING OF: